[mustang11]

95 gt. The temp gauge has been acting weird going back and forth. When i first start the car it will work its way up to middle then eventually all the way to hot. So i get out and their is no steam or anything i even put my hand on the top of the engine and it isnt even warm. I have the advance set to 15 with 91 octane. All stock. All of my other gauges seem to work fine and i recently replaced my thermostat and have full coolant.

[HISSIN50]

How recently did you have the system open? Air in the system can cause erratic gauge readings.

[nmcgrawj]

Take off the radiator cap and just run it open for a while and let the thermostat cycle open and closed. Squeeze the upper radiator hose just to give any air in the system extra motivation to move. If that doesnt work you may want to hook up an aftermarket temp gauge just to see exactly what its doing.


Does it stay on "hot" once it goes up? What thermostat did u put in? Are you sure its opening?

[mustang11]

i dont know what brand of thermostat i put in but i bought it at napa and it was the more expensive one. The guage will start out at cold then slowly work up to eventually getting to hot. But before my new thermostat was put it it overheated and was steaming and the guage didnt even read all the way hot. And now it reads all the way hot but i can touch the engine. when i turn off the car it goes back to cold and raises slowly.

[nmcgrawj]

Get an aftermarket gauge on there or replace the factory temperature gauge sender....


If the gauge reads hot, yet the engine isnt hot....then something isnt right. Is ANY part of the cooling system hot? Radiator? DOes it blow hot air?

[Chythar]

Sounds to me that the CTS (coolant temperature sensor) may have failed, or the connection is loose. The CTS is the brass sensor just to the right of the distributor. It has a black "L" shaped rubber plug on it. Inside the plug are two metal pieces that grip the CTS. Try to squeeze the plug so the metal pieces are closer together. See if that helps.

It would help if you had a code reader that can read PIDs (engine sensors, basically). You could then see the temperature that the computer sees. Where do you live, mustang11? If you're in Los Angeles somewhere I can help you out.

[revhead347]

Sounds like it could be a blown head gasket. My gauge did the same thing when I blew the head gasket.

Kurt

[ttocs]

mine did the same thing when I replaced the thermostat because I didn't get the air out of the system. AS they said get the car up to temp with the cap off and squeeze the upper hose to work the bubble through that forms in that hose.

if that doesn't work then you can start throwing parts at it, but start simple.

[mustang11]

when i took the radiator cap off and drove it coolant shot out the cap all over the place. so i put it back on and drove it for awhile then the gauge went to hot again but no steaming from engine or anything still cool enough for me to put my hand on it. But when i parked i heard gurgling in the coolant resivoir. when i pinch the little hose that goes from the radiator cap to the coolant reservior it stops gurgling.

[ttocs]

Originally Posted by mustang11

when i took the radiator cap off and drove it coolant shot out the cap all over the place. so i put it back on and drove it for awhile then the gauge went to hot again but no steaming from engine or anything still cool enough for me to put my hand on it. But when i parked i heard gurgling in the coolant resivoir. when i pinch the little hose that goes from the radiator cap to the coolant reservior it stops gurgling.

Oh man, You are supposed to sqeeze the upper radiator hose while you are driving it with everything spraing out.

just kidding DUDE, did I say anywhere in the instructions to drive it with the cap off? You are supposed to do all that with it idleing........

now go back out and fill yer radiator back up, check the coolant level and then repeat my instructions. This time just let the car idle until it heats up(with the cap off). DO NOT DRIVE IT but once you feel the upper hose heat up, just give it a couple of light sqeezes. That gurgling noise you heard was the air escaping. Went that bubble gets through the system, and back out the cap you should be fine.

[mustang11]

i did the radiator cap thing. It blows hot air at first then sometimes warm. The temp of the air blowing from the heater gets warm then hot then warm. If i turn the heater off for a while then turn it on it blows way hot air then when i leave on it gets way cooler.

[SableSal]

You have air in the system. Do as mentioned above and you'll be good.

[mustang11]

did as you guys said and it fixed the problem

[nmcgrawj]

Originally Posted by mustang11

did as you guys said and it fixed the problem

glad to hear! What exactly fixed it?